1. Technical Field
The present invention relates to an organic photoreceptor.
2. Description of Related Arts
Since an organic photoreceptor has such advantages as broader selection range of source materials, better environmental compatibility, lower production cost, etc. compared to an inorganic photoreceptor, such as a selenium photoreceptor, and an amorphous silicon photoreceptor, it has been recently becoming a mainstream of an electrophotographic photoreceptor replacing the position of an inorganic photoreceptor.
By an image formation method based on the Carlson method, an organic photoreceptor is charged, an electrostatic latent image is formed, a toner image is formed, and then the toner image is transferred to a transfer paper, which is fixed to form a final image.
While, in a recent image formation method, digitalization has advanced, and for formation of an electrostatic latent image on an organic photoreceptor, an image formation method using laser light as an exposing source is widely employed. Further, a high-definition image formation method using shortwave laser light having the oscillation wavelength of 500 nm or less as an exposing source has been recently proposed.
Meanwhile, the use of an image formation method according to exposure by shortwave laser light overlaps the uses as a printer requiring high image quality and large quantity printing and a high speed color printer, and therefore an organic photoreceptor to be used in the image formation method is required to have properties for an electrophotographic photoreceptor with high image quality and high durability suitable for latent image formation by shortwave laser light and high speed printing.
In this connection, an organic photoreceptor has a drawback in that the surface thereof tends to wear due to friction with a contacting component such as a cleaning component. To prevent such wear deterioration of the surface layer, a photoreceptor using a polycarbonate resin with high abrasion resistance, such as a polycarbonate resin having a cyclohexylene group (also called as polycarbonate Z), as a binder for a charge transport layer, has been proposed (JP-A-60-172044).
However, the improvement of the abrasion resistance of an organic photoreceptor by using the binder was not satisfactory, and especially if a charge transport compound is added in the surface layer (protection layer), the improvement effect was limited.
Further, in order to improve the abrasion resistance of a photoreceptor, a photoreceptor provided with a protection layer of a cross-linked cured resin composed of a composition of an acrylic polymerizable compound, a charge transport compound having a polymerizable functional group, and a metallic oxide particle treated with a surface preparation agent having a polymerizable functional group on the surface layer of a photoreceptor, has been proposed (JP-A-2010-169725).